vioctrl
Used to drive freeze signals to HPS VIO banks.
The register array index corresponds to the freeze channel.
Freeze channel 0 provides freeze signals to VIO bank 0 and 1.
Freeze channel 1 provides freeze signals to VIO bank 2 and 3. Only drives freeze signals when SRC.VIO1 is set to SW.
Freeze channel 2 provides freeze signals to VIO bank 4.
All fields are only reset by a cold reset (ignore warm reset).
The following equation determines when the weak pullup resistor is enabled:
enabled = ~wkpullup | (CFF & cfg & tristate)
where CFF is the value of weak pullup as set by IO configuration
| Module Instance | Base Address | Register Address |
|---|---|---|
| sysmgr | 0xFFD08000 | 0xFFD08040 |
Offset: 0x40
Access: RW
Important: To prevent indeterminate
system behavior, reserved areas of memory must not be accessed by software or
hardware. Any area of the memory map that is not explicitly defined as a register
space or accessible memory is considered reserved.
| Bit Fields | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 |
Reserved |
|||||||||||||||
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Reserved |
slew RW 0x0 |
wkpullup RW 0x0 |
tristate RW 0x0 |
bushold RW 0x0 |
cfg RW 0x0 |
||||||||||
vioctrl Fields
| Bit | Name | Description | Access | Reset | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 4 | slew | Controls IO slew rate
|
RW | 0x0 | ||||||
| 3 | wkpullup | Controls weak pullup resistor
|
RW | 0x0 | ||||||
| 2 | tristate | Controls IO tri-state
|
RW | 0x0 | ||||||
| 1 | bushold | Controls bus hold circuit
|
RW | 0x0 | ||||||
| 0 | cfg | Controls IO configuration
|
RW | 0x0 |